This program project will establish, administer, and facilitate joint research activity across the lALSA and HALCyon research networks, involving key investigators and research teams from over 40 major longitudinal studies on adult development and aging. This Administrative Core will exercise overall coordination of the program project, including the development and maintenance of infrastructure, coordination among projects and cores, and provision of overall grants management. Each of the Subprojects in this proposed program emphasizes critical substantive issues in the study of aging-related changes: the administrative core will serve to facilitate synergy across these Subprojects and Cores. A vital function of this application is to develop further, maintain, and make use of an infrastructure for collaborative analysis of international longitudinal study data and facilitate broad dissemination of analytical and substantive knowledge to gerontological researchers. This Core will be responsible for planning of working meetings at national and international conferences to provide a forum for the dissemination and discussion of results and to act as a catalyst for the further development and analysis of affiliated studies. In addition, The Administrative Core will encourage early career investigators (including graduate students and postdoctoral fellows) to be involved in lALSA/HALCyon projects, obtain research training, and present results at annual meetings.